A multilayer ceramic capacitor, a multilayer electronic component, is a chip type condenser mounted on the circuit boards of various electronic products, including display devices such as liquid crystal displays (LCDs), plasma display panels (PDPs), and the like, computers, personal digital assistants (PDAs), mobile phones, and the like, serving to charge or discharge electricity.
This multilayer ceramic capacitor (MLCC) may be used as a component in various electronic apparatuses due to advantages thereof such as a small size, high capacitance, and ease of mountability.
The multilayer ceramic capacitor may have a structure in which a plurality of dielectric layers and internal electrodes disposed between the dielectric layers and having different polarities are alternately stacked.
Since the dielectric layer as described above has piezoelectricity and electrostriction, when a direct current (DC) or alternating current (AC) voltage is applied to the multilayer ceramic capacitor, a piezoelectric phenomenon may occur between the internal electrodes, thereby generating vibrations.
These vibrations are transferred to a circuit board on which the multilayer ceramic capacitor is mounted through external electrodes of the multilayer ceramic capacitor, such that an entire circuit board becomes a sound reflecting surface to transmit the sound of vibrations as noise.
The sound of vibrations may correspond to an audio frequency within a range of 20 to 20,000 Hz potentially causing user discomfort. The vibration noise causing listener discomfort as described above is known as acoustic noise.
In accordance with the recent trend for slimness and miniaturization of electronic devices, the multilayer ceramic capacitor has been used together with a printed circuit board in high voltage and large voltage change environments, and thus, such acoustic noise may be experienced by a user.
Therefore, a novel product capable of reducing acoustic noise has been continuously demanded.
Meanwhile, research into a composite electronic component in which a printed circuit board is used below a multilayer ceramic capacitor in order to reduce acoustic noise has been conducted.
However, in a case of increasing a thickness of the circuit board, an effect of reducing acoustic noise may be increased, but a side effect of decreasing electrical properties may occur. Therefore, research into a technology capable of efficiently reducing acoustic noise while significantly decreasing the thickness of the circuit board has been required.